How do you estimate a difference to the nearest tenth?

Answer 1

Sometimes it is advantageous to express a value in round numbers. To round to a particular place, look at the digit immediately to the right of the one you want to round to, in this case, the hundredths place. If that digit is 4, 3, 2, 1 or 0, zero it and everything to the right of it out. If that digit is 5, 6, 7, 8 or 9, increase your target digit by one and zero everything to the right of it out. If your target digit is 9, it will become a zero and increase the digit to the left of it by one.

10.6852 - 7.3599 = 3.3253 which rounds to 3.3

Put another way, 10.7 - 7.4 = 3.3